Home / 21,320.80-31,939.64-12,980.13

Finding the Fourth Proportional to 21,320.80, 31,939.64 and 12,980.13

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Solution

The fourth proportional to 21,320.80, 31,939.64 and 12,980.13 is: 19,444.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    21,320.80 : 31,939.64 = 12,980.13 : x
  2. Step 2: Convert to fraction form
    21,320.80/31,939.64 = 12,980.13/x
  3. Step 3: Cross multiply
    21,320.80x = 31,939.64 × 12,980.13
  4. Step 4: Simplify right side
    21,320.80x = 414,580,614.45
  5. Step 5: Solve for x
    x = 414,580,614.45/21,320.80
  6. Step 6: Final answer
    x = 19,444.89

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.